Wonderbags Greater Gauteng Area. A Wonderbag is a heat-retention cooking bag. It is an insulated bag in which people can cook anything from meaty stews or vegetable curries to simple rice and soups. You heat up your pot of food on the stove, kick-starting the cooking process, and then place it in the Wonderbag. For Orders & Inqueries: WonderbagBoys@gmail.com Wonderbagboys are the most wide spread ...